I. Science

During the 1960s, evolutionary biologists such as Hamilton and Williams developed the first theories concerning the evolution of altruism. These theories define altruism as any type of behavior that (1) diminishes the Darwinian fitness of its bearer and (2) increases the fitness of other organisms; this fitness is defined as the success of an organism (or phenotype or genotype) in producing sexually mature descendants relative to the average success of the fertile population (C.R. Darwi…